Vehicle with self-contained load transfer system

ABSTRACT

A trailer with a self-contained load-transfer system. The trailer includes a frame, and a suspension supporting the frame which can be adjusted selectively to change the frame&#39;&#39;s elevation above the ground. Incorporated in the frame are transversely extending track members, adjacent opposite ends of which are mounted laterally shiftable and vertically swingable track extenders that can be moved to positions forming longitudinal extensions to the track members. The extenders are adapted for connection (when extended) to supports external to the trailer, and when so connected swing between raised and lowered positions relative to the frame with lowering and raising, respectively, of the frame relative to the ground. Such swinging functions in cooperation with track-riding carriages that can be detachably connected to the base of a load to accommodate picking up and depositing of a load on the frame. The carriages, track members and extenders facilitate lateral shifting of a load relative to the frame.

United States Patent [19] Schmidt July 3,1973

[ VEHICLE WITH SELF-CONTAINED LOAD TRANSFER SYSTEM Kenneth J. Schmidt,Thurston, Oreg.

[73] Assignee: General Trailer Company, lnc.,

Springfield, Oreg.

[22] Filed: Aug. 4, 1971 [21] App]. No.: 168,980

[75 Inventor:

Primary Examiner-Robert G. Sheridan Attorney-Kolisch, Hartwell &Dickinson [57] ABSTRACT A trailer with a self-contained load-transfersystem. The trailer includes a frame, and a suspension supporting theframe which can be adjusted selectively to change the frames elevationabove the ground. incorporated in the frame are transversely extendingtrack members, adjacent opposite ends of which are mounted laterallyshiftable and vertically swingable track extenders that can be moved topositions forming longitudinal extensions to the track members. Theextenders are adapted for connection (when extended) to supportsexternal to the trailer, and when so connected swing between raised andlowered positions relative to the frame with lowering and raising,respectively, of the frame relative to the ground. Such swingingfunctions in cooperation with track-riding carriages that can bedetachably connected to the base of a load to accommodate picking up anddepositing of a load on the frame. The carriages, track members andextenders facilitate lateral shifting of a load relative to the frame.

4 Claims, 8 Drawing Figures PATENTEDJUL 3 I975 sum 2' or .3

a Kenneih J. Schmid-i' BY V IN V E N TOR 444%, 44.42; v ju PATENTEUJUL 3I973 SHEET 3 BF 3 Kennelh J. Schmicll' BY INVENTOR Mi AQWV 3 VEHICLEWITH SELF-CONTAINED LOAD TRANSFER SYSTEM BACKGROUND AND SUMMARY OF THEINVENTION This invention pertains to a load-transporting vehicle, andmore particularly to a self-contained loadtransfer system in such avehicle. For the purpose of illustration herein, a preferred embodimentof the invention is described in conjunction with a trailer fortransporting prefabricated modular home units.

Various types of relatively large and bulky, essentially unitized, loadsare now transported from point-topoint by trailers hauled behindconventional heavy duty tractors. One type of load of this generaldescription which has become of interest in recent years is a so-calledmodular home unit. Such a unit typically comprises an elongatedpreassembled portion of a home, which portion is intended to betransported from its fabrication site to a foundation site where it willbe joined with one or more additional units to make up the final home.Such a unit normally comprises relatively conventional wood frameconstruction, and typically has a width either of about 12 or 14 feet,and a length of about 48, 52 or 60 feet.

The handling and transporting of such a unit presents a number ofproblems which heretofore have not been taken care of completelysatisfactorily. One of the principal handling difficulties encounteredwith such a unit is how properly and safely to transfer the unit intoand off of the transporting trailer or truck frame. The large size andrelative fragility and nonrigidity in such a unit makes this kind ofoperation especially tricky. A unit improperly supported or moved duringsuch an operation can easily twist, crack or otherwise be damaged.

A general object of the present invention therefore is to provide anovel on-board load-transfer system in a transporting vehicle whichaccommodates relatively simple and safe on and off loading of a load,such as a unit of the type described above, in a practical andsatisfactory manner.

More specifically, an object of the invention is to provide such asystem which employs in a vehicle the novel combination of a verticallyadjustable suspension that is operable to raise and lower theload-supporting frame in the vehicle, and a track arrangement in theframe including vertically adjustable portions which, with raising andlowering of the frame, work in conjunction with carriages automaticallyto pick up and deposit a load relative to the frame.

According to a preferred embodiment of the invention, a trailer or likeframe is provided with a support ing suspension which can be adjustedselectively to change the frame's elevation above the ground. In thespecific embodiment disclosed herein, the suspension means comprises airgags whose levels of inflation can be changed. Incorporated rigidly inthe frame are transvcrsely extending track members, adjacent oppositeends of which are mounted laterally shiftable and vertically swingabletrack extenders that can be moved outwardly and upwardly to positionsforming longitudinal extensions to the track members. The trackextenders are adapted for connection (when extended) to supportsexternal to the frame, and when so connected, swing between raised andlowered positions relative to the frame with lowering and raising,respectively, of the frame relative to the ground.

Such swinging of the track extenders functions in cooperation withtrack-riding carriages, that can be detachably connected to the base ofa load, to accommodate picking up and depositing of a load relative tothe frame. The carriages, track members, and track extenders facilitatelateral shifting of a load relative to the frame.

DESCRIPTION OF THE DRAWINGS These and other objects and advantagesattained by the invention will become more fully apparent as thedescription which follows is read in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a perspective view, somewhat simplified, illustrating atrailer containing a load-transfer system as contemplated herein, withthe trailer positioned adjacent a foundation, and with a modular homeunit that has been carried on the trailer shown in a condition beingoff-loaded from the tailer onto the foundation;

FIG. 2 is a fragmentary side elevation, on a larger scale than FIG. 1,illustrating an adjustable suspension provided for the frame in thetrailer in FIG. 1;

FIGS. 3, 4 and 5 are rear longitudinal axial views of the trailer inFIG. 1, in about the scale as FIG. 2, further illustrating the system ofthe present invention, and showing successive stages in an unloadingoperation;

FIG. 6 is a fragmentary side elevation, on a larger scale than FIGS. 3,4 and 5, illustrating details of a track and a track extender ascontemplated herein;

FIG. 7 is a view taken generally along the line 7-7 in FIG. 6; and

FIG. 8 is a fragmentary view, on a larger scale than FIGS. 6 and 7,taken generally along the line 88 in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION Turning now to the drawings, andreferring first to FIG. 1, indicated generally at 10 is an elongatedground-traveling trailer which incorporates an onboard load-transfersystem as contemplated herein. The trailer includes a front end 10a,which is toward the viewer in FIG. 1, and a rear end 10b, which is awayfrom the viewer in the figure. Trailer 10 is adapted to handle modularhome units of the type outlined above, and such a unit is showngenerally in dash-dot outline at 12 in FIG. 1, in a condition partiallyunloaded from the trailer onto the near side of an adjacent foundation14 alongside of which the trailer has been parked. For the purpose ofsimplifying FIG. 1, the trailer is shown in a condition uncoupled fromthe usual hauling tractOI.

Unit 12 is a half-home unit having a width W of about 12 feet and alength L of about 48 feet. This unit is adapted to be placed on thehalf-side of foundation 14 which is directly adjacent trailer 10, and isfurther adapted to be joined with another similar unit placed on theother half-side of the foundation.

Foundation 14 is conventional in construction, including a rectangularpoured concrete perimeter wall 16, and a longitudinal center beam 18which is supported on concrete pillars 20. Wall 16 includes spacedapartparallel ends 16a, 1611 which are about 24 feet long, joined withspaced-apart parallel sides 16c, 16d which are about 48 feet long.Suitably mounted on the tops of the ends and sides in wall 16 areconventional elongated wooden sills 22. The top surfaces of sills 22 andbeam 18 occupy a common, substantially horizontal plane which is at anelevation of about 30 inches above the level of the ground underlyingtrailer 10.

The trailer, parked as shown in FIG. 1, is disposed with itslongitudinal axis substantially parallel to side 16d in wall 16 and at adistance of about 7 feet from this side. In addition, the trailer ispositioned with the opposite ends of unit 12 properly aligned withopposite ends 16a, 16b in wall 16.

Considering the construction of trailer 10, and referring to FIGS. 1 and2, the trailer includes: an elongated frame 24; a plurality (namely six)of vertically adjustable suspensions, such as those shown at 28 in FIG.2, which carry conventional axle-mounted wheel sets 28; and a verticallyadjustable drawbar mechanism 30 (see FIG. 1). Wheel sets 28 support therear portion of the frame for travel over the ground, and thus arereferred to herein also as ground-traveling supportmeans. The frontportion of the trailer frame, with the latter traveling over the ground,is normally supported through drawbar mechanism 30 on the frame of aconventional hauling tractor, to which the lead end of the drawbarmechanism is suitably coupled. However, with the trailer parked, asshown in FIG. 1, detached from any tractor, the front portion of frame24 is supported by a conventional crank-operated adjustable supportmechanism 32 which is mounted adjacent the front end of the drawbarmechanism.

Except to the extent that will bedescribed hereinafter, frame 24 isrelatively conventional in construction. The particular frameillustrated is what might be thought of as a sectionalized frame whichis constructed for both longitudinal and lateral extension andcontraction, thus enabling it readily to accommodate modular home unitsof different sizes. The frame thus includes suitably longitudinallytelescopically joined front, central and rear sections 24a, 24b, 240,respectively, the opposite sides of which carry telescopically mountedlateral extension members 34. The

three sections in the frame each comprise a rigid unit formed from theusual interconnected longitudinal and transverse members, braced bysuitable braces. The lateral extension members are slidably received intransversely extending tubes provided in the various frame sections,such tubes, in some cases, forming structural transverse members in thesections. The outer ends of extension members 34 carry upwardlyprojecting retainer plates, such as those shown at 36, which preventlateral slippage of a load carried on the trailer.

By adjusting the positions of front and rear frame sections 24a, 240 oncentral section 24b, the length of frame 24 can be adjusted between aminimum of about 37 feet, the frame being illustrated herein with alength of about 48 feet, and a maximum of about 57 feet. Similary,through adjusting the positions of the lateral extension members on thevarious frame sections, the overall width of the frame can be adjustedbetween a minimum of about l2 feet and a maximum of about l4 feet. Asillustrated herein, the extension members are adjusted to give the framean overall width of about 12 feetsuitable for handling home unit 12.Appropriate conventional means is, of course, provided for releasablelocking the frame sections and extension members in different desiredpositions relative to one another.

It is thus apparent that frame 24 can be adjusted to provide what mightbe thought of" as a load-support deck which may be as small as about 12feet by 37 feet,

and as large as about 14 feet by57 feet. Home units having widths up toabout 14 feet can thus be readily taken care of. Home units havingalength greater than 57 feet, and up to about 60 feet, can also be takencare 7 of, with an end of the unit, with the unit supported on thetrailer, overhanging the rear end of the trailer frame. In order toassure proper balancing of a load on the frame, it is customary toadjust the lateral extension members whereby the width of theload-support deck which they define is substantially centered laterallywith respect to the longitudinal axis of the frame. Members 34 are shownso adjusted herein.

Joined rigidly in frame 24, according to the present invention, arethree elongated transversely extending track members, shown at 38, 40,42. These track members are each about 8 feet long herein, and compriseelongated, hollow, substantially rectangular cross section tubes. Member38 is provided in frame section 24a adjacent the front end thereof,member 40 in frame section 24b immediately in front of the forwardmostwheel sets 28, and member 42 in section 24c adjacent the'rear endthereof. These track members may, and in the case being described do,form integral transverse structural parts of the particular framesections in which they are included. The top surfaces of these trackmembers are referred to herein as track surfaces.

Referring to FIGS. 6 and 7 along with FIG. 2, suitably joined to andextending along the top surfaces of members 38, 40, 42, substantiallycentrally thereon (relative to the opposite sides of the surfaces), areelongated inverted angle iron members, such as angle iron member 44shown in FIG. 2 on the top surface of track member 40. Further, providedin such surfaces, adjacent opposite ends of the track members, arerectangular notches, such as notch 40a shown in FIGS. 6 and 7 adjacentthe right end of member 40 in the figures. These notches each have alength (measured longitudinally of the associated track member) of about6 to 7 inches, and a width of about 3 inches. The angle iron members onthe various track members extend between the inner ends of the notchesin the members. This can be seen clearly in FIGS. 6 and 7 with respectto the right end of angle iron member 44 and the inner left end of notch40a.

Also provided in frame 24 according to the present invention are threepairs of elongated track extenders 46, 48, 50 for track members 38, 40,42, respectively. These track extenders are .substantially the same inconstruction, and one of extenders 48 is shown in detail in FIGS. 6, 7and 8. Extender 48 comprises an elongated tubular arm 52 having a lengthslightly less than 4 feet herein, and a side configuration asillustrated in FIG. 6. Joined to the base of arm 52, adjacent the leftend thereof in FIGS. 6 and 7 is a block 54. Joined to the top surface ofarm 52, as shown in FIGS. 6 and 7, is an elongated plate 58. Theopposite sides of the left end of this plate in FIGS. 6 and 7 arenotched to provide a reduced-width end projection 56a which is adaptedto fit within notch 40a.-Projection 56a has a length slightly less thenthe length of notch 40a, and a width slightly less than the width of thenotch. It will be noted that with the various parts in the relativepositions shown in FIGS. 6 and 7, the left end of projection 56aterminates short of the left end of notch 40a. Plate 58 has a thicknesswhich is substantially the same as the thickness of the upper wall inthe tube forming track member 40. i

The top surface of plate 56 herein constitutes a track extensionsurface. Joined centrally to and extending along this surface is aninverted angle iron member 58 whose cross-sectional configuration anddimensions are substantially the same of those of the angle iron memberspreviously mentioned.

The track extenders are slidably and telescopically received within thehollow interiors of their respective associated track members. It willbe noted, for example, in FIGS. 6 and 7 that the left end of extender 48in these figures is freely received within the hollow interior of member40. According to the present invention,

the track extenders are adapted to be shifted between retracted andextended positions, and also between lowered and raised positions. Thesevarious positions are illustrated clearly in FIG. 6 for the trackextender 48 shown therein.

More specifically, extender 48 is shown in solid outline in an extendedand raised position. In this position, the extender extendslongitudinally outwardly from member 40, with block 54 bearing againstthe bottom wall in member 40, and with the upper left end of extender 48bearing against the inside of the upper wall in member 40. The topsurfaces of plate 56 and of member 40 are longitudinally andhorizontally aligned, with angle iron members 44, 58 also so aligned.Projection 56a is received within notch 40a. In dashed outline at 48A inFIG. 6, extender 48 is shown in an extended but lowered position, withthe extender essentially completely supported on the bottom wall inmember 40. In its lowered position, extender 48 can be shifted freelyinto and out of member 40, and in particular, can be shifted inwardly toa retracted position such as that shown in dash-double-dot outline at483 in FIG. 6. The track extender can be locked in its retractedposition in any suitable manner, as by extending a pin through pairs ofsuitably aligned accommodating bores 51, 53 provided adjacent the outerends of member 40 and arm 52, respectively.

Referring to FIG. 2, previously mentioned suspensions 26 are mounted onframe section 24b. According to the present invention, and as wasalready briefly mentioned herein, these suspensions are verticallyadjustable, whereby they may be adjusted to change the elevation offrame 24 above the ground. Preferably, suspensions 26 each comprise anextensiblecontractible air bag whose level of inflation may be changedto bring about the adjustment mentioned. Accordingly, suspensions 26each include an air bag, such as those shown at 60, which acts generallyvertically between overlying members in frame section 24b and the pairof wheels in a wheel set 28. More specifically, an air bag 60 actsbetween such frame members and a pivoted rock structure, such as rockstructures 62, which is pivoted to frame section 24b and which carriesaxles supporting the wheels in a wheel set. A suspension including anair bag is preferred because of the cushioning which such a bag providesfor a trailer frame, and also because of the relative ease with whichthe level of inflation of the bag may be changed to produce theadjustment mentioned. A detailed description of a suspension, such assuspensions 26, is found in my priorfiled copending U. S. application,Ser. No. 112,135, filed Feb. 3, 1971, now U.S. Pat. No. 3,704,898,entitled Vehicle Axle Suspension.

It should be understood that while a specific type of adjustablesuspension has been described herein, with reference made to aprior-filed patent application fully disclosing the constuction of sucha suspension, various types of vertically adjustable suspensions, withand without air bags, may be used. What is important in the presentinvention is that the suspensions which are used in the trailer becapable of being adjusted to place the trailer frame at differentselected elevations above the ground. In the particular suspensiondescribed herein, such an adjustment is made, as has already beenmentioned, simply by changing the levels of inflation in air bags 60. Intrailer 10, through changing these inflation levels, suspensions 26 maybe adjusted to place the top of frame 24 at any selected elevationbetween about 24 inches and about 36 inches above the ground. In FIG. 1the trailer frame is shown adjusted to a vertical position with the topsurfaces of track members 38, 40, 42 above the plane containing the topsurfaces of sills 22 and beam 18.

The track members, track extenders, and vertically adjustablesuspensions herein all form parts of onboard load-transfer apparatus intrailer 10.

Referring again to FIG. 1, drawbar mechanism 30 comprises an elongatedrigid subframe 64 formed from a pair of rearwardly diverging elongatedmembers 66. In addition, the drawbar mechanism includes an inflatableair bag 68 which acts between subframe 64 and the front end of trailerframe section 24a. Previously mentioned support mechanism 32 is suitablymounted adjacent the forward ends of members 66. The rear ends ofmembers 66 are pivoted to a transverse member in frame section 24athrough transversely aligned pivot connections, such as the pivotconnection shown at 70. Pivot connections 70 mount subframe 64 forswinging in an upright plane with changes in the level of inflation inair bag 68.

Suitably anchored to the frontends of members 66 in subframe 64 is aconventional hitch ring 72 which accommodates attachment to the frame ina hauling tractor.

Details of a drawbar mechanism substantially the same as mechanism 30are described in my prior filed copending U. S. application, entitledTrailer With Independently Adjustable-l-Ieight Frame and Drawbar Means,Ser. No. 154,336, filed June 18, 1971. Other types of drawbar mechanismmay, of course, be used.

Other equipment illustrated in the drawing figures will be describedalong with the description which now follows of the way in which thesystem of the present invention may be used. Let us assume initiallythat home unit 12 has been suitably loaded onto the trailer for haulingto the site of foundation 14. The manner in which the home unit issupported on the trailer during hauling is illustrated in FIG. 3. Inthis figure, it can be seen that unit 12 is supported in a laterallycentered position on frame 24 through blocks, such as blocks 74, whichare suitably attached, as by nailing, to the base of the unit alongopposite sides thereof. Blocks 74 rest on the outer ends of extensionmembers 34, with retainer plates 36 guarding against lateral slippage ofthe unit. Through adjustments in the levels of inflation of air bags 60,68, the desired running height may be established for frame 24, suchrunning height being illustrated in FIG. 3 as being about 25 or 26inches above the ground. Normally, the air bags are adjusted to assurethat the frame offers a substantially level and horizontal load-supportdeck for a load.

The trailer, so loaded, is then hauled to the site of foundation l4, andis maneuvered to place it alongside and parallel to the appropriatefoundation wall side,

' such as side 16d. More specifically, the trailer is maneuvered to aposition with its longitudinal axis substantially parallel to and spacedfrom this wall side. As was indicated earlier, it is important that unit12 be positioned with its opposite ends aligned with the opposite endwalls l6a,-l6b in the foundation.

Aligned pairs of foundation tracks are then set up inside thefoundation, as is illustrated in FIGS. 1 and 4. Each foundation trackmay comprise an elongated beam 76, similar in cross section to trackmembers 38, 40, 42 in the frame, on top of which are joined centrallydisposed elongated inverted angle iron members 78 which are similar tothose previously described. Beams 76 are set up in axially aligned pairson hydraulic jacks 80 on opposite sides of foundation beam 18, with eachaligned beam pair aligned with a different track member in the trailerframe. The top surfaces of beams 76, which also form track surfacesherein, are adjusted to a common elevation slightly above the level ofthetop surfaces of sills, 22 and beam 18.

Thereafter mounted on foundation beam 18, at the locations of theconfronting ends of beams 76, are suitable track joiners 82 whichprovide .connecting track surfaces between those on the beams.Similarly,

mounted on the sill which is on top of foundation wallside" 16a aretrack joiners 84 which define track surfaces over this sill.Trackjoiners 84 are located adjacent the near ends of the nearest set ofbeams 76 in FIG. 1. Track joiners 82, 84 preferably include flat plates,the upper surfaces of which define track s'urfaces, with angle ironmembers like those already described herein joined centrally to theseplates. The joiners also include suitable spaced-apart'side plates whichjoin with the first-mentioned plates and are shaped to clip securelyover beam 18 and sills 22.

' Beams 76, jacks 80, and track joiners 82, 84, when not set up for use,are carried on trailer 10.

Referring to FIG. 4, withv the trailer properly positioned relative tofoundation l4, and with the foundation tracks and joiners set up, airbags 60, 68 are extended to raise frame 24 as illustrated in the figure.Track extenders 46, 48, 50 are then unlockedfrom their respectiveassociated track members, and are shifted longitudinally outwardlytoward their extended and lowered positions. This situation is clearlyillustrated in FIG. 4. The outer ends of the extenders which are awayfrom foundation 14 are then each connected by means of a pin, such aspin 86 shown in FIG. 4, to an upright external support device, such asdevice 88, which is placed on the ground adjacent and along-side thetrailer. Devices 88 preferably accommodate such attachment at severaldifferent elevations thereon. The outer ends of the track extenderswhich are adjacent the'foundation are pinned to track joiners 84.

Carriages as contemplated herein are then attached to the underside ofunit 12 in the regions where the unit extends laterally beyond trackmembers 38, 40, 42, and over track'extenders 46, 48, 50. Such carriagesare shown generally at 90 in FIGS. 4, 5 and 8, with details of carriageconstruction'clea'rly illustrated in the latter figure. As can be seenin FIG. 8, a carriage comprises an elongated beam 92 on the oppositesides of the center of which are mounted grooved wheels 94. Eachcarriage comprises a pair of such wheels. A wheel 94 includes a centralgroove 94a on opposite sides of which are rims 94b. The cross-sectionalconfiguration of a groove 94a is adapted to match with the exposedsurfaces of an inverted angle iron member herein. Rims 94b are adaptedto ride on the track surfaces described herein, and further are adaptedlaterally to overlap the opposite sides of notches, such as notch 40a,and projections, such as projection 56a.

Slidably mounted on the opposite ends of a beam 92 in a carriage areattaching members 96 which are shaped to receive the bases of joists ina home unit. Tighteners 98 on members 96 may be used to secure thelatter against sliding on a beam. In FIGS. 4, 5 and 8, carriages areshown in conditions attached to joists 100 in home unit 12. Six suchcarriages are employed herein.

With carriages 90 mounted in place as just described, airbags 60, 68 aredeflated to relower frame 24. With such lowering of the frame, and withthe outer ends of the track extenders attached as described to supportsexternal to the frame, the track extenders swing upwardly toward theirraised positions, in which positions they are illustrated in FIG. 5.Onthe track extenders attaining such positions, they form longitudinalextensions to the track members in frame 24. Upward swing- 'the wheelsreceiving the angle iron members on the extenders, and with consequentlifting of the carriages and lifting of unit 12 off of members 34. Withsuch lifting of unit 12, blocks 74 may be removed.

It will be apparent that under these circumstances there now exist threeelongated tracks extending between and over the trailer and foundation,which tracks readily accommodate lateral shifting of unit 12 off of thetrailer and onto the foundation. Such lateral shifting may beaccomplished in any suitable manner, with the wheels in the carriagesriding on the various track surfaces described herein, and preventedfrom derailing from such surfaces due to engagement of the groovesin thecarriage wheels with the angle iron'members. In particular, unit 12 isshifted to a position over foundation 14 such as that illustrated indash-dot outline at 12A in FIG. 5.

With unit 12 properly positioned over the foundation it may readily belowered onto the foundation by lowering jacks 80 and beams 76. Prior tocomplete lowering of the jacks, track joiners 82, 84 may be removed.And, after placing of the unit onto the foundation, beams 76 and jacks80 may be removed and returned to the trailer. The track extenders maythen be returned to their retracted positions within the track membersin frame 24, and support devices 88 suitably stored on the trailer.

It is thus apparent that the system described herein permits relativelysimple shifting of a load onto and off of a vehicle such as a trailer10. Obviously, while an unloading operation has been describedspecifically, a loading operation is similar. With the track members andtrack extenders constructed as described, and with frame 24 supportedthrough vertically adjustable suspensions, raising and lowering of aload, such as a mod- Loads having different dimensions than thosespecifically mentioned herein can, of course, be handled-the specificdimensions of the various parts in the vehicle described herein notbeing critical.

While an embodiment of the invention has been described herein, it isappreciated that variations and modifications may be made withoutdeparting from the spirit of the invention.

I claim:

1. in a ground-traveling load-transporting vehicle including anelongated frame defining an elongated loadsupport deck, andground-traveling support means for supporting the frame for travel overthe ground, apparatus facilitating the transfer of a load onto and offof said deck comprising means adjacent said deck defining an elongatedtrack which extends transversely of the frame s longitudinal axis,opposite ends of said track terminating short of the opposite side ofsaid deck,

a pair of elongated movable track extenders mounted on said frameadjacent the opposite ends of said track for movement between extendedand retracted positions and between raised and lowered positions, eachtrack extender when in its said extended and raised positions forming alongitudinal extension to an end of saidtrack,

means on each track extender accommodating detachable connection thereofto a support external to said vehicle,

adjustable suspension means operatively interposed between said frameand said ground-traveling support means adjustable to suspend the formeron the latter at different selected elevations above the ground,

adjustment of said suspension means producing movement of said trackextenders between their said raised and lowered positions with theextenders extended and connected to external supports, and

at least a pair of carriages each ridable on said track and trackextenders and each adapted to be detachably connected to a load on saiddeck in the space under the load where such extends beyond an end ofsaid track, each carriage further being adapted to be picked up by anunderlying track extender, thus to pick up the load, with the trackextender extended and with adjustment of said suspension means whichproduces movement of the track extender from its said lowered toward itssaid raised position.

2. The vehicle of claim I, wherein said means defining said trackcomprises an elongated tube, and said track extenders are freely andslidably received within opposite ends of said tube.

3. The vehicle of claim 2, wherein each track extender is shaped toaccommodate limited vertical rocking thereof relative to said tube withthe former extended from the latter.

4. An on-board system for transferring a load onto and off of a vehicle,where the vehicle includes an elongated frame defining an elongatedsupport bed for a load, and means supporting the frame for travel overthe ground and for adjustment to different elevations above the ground,said system comprising a plurality of elongated track members disposedtransversely of said frames longitudinal axis and rigidly joined in theframe at points distributed along the length of said support bed, eachtrack member terminating short of the opposite sides of said bed andincluding an upwardly facing generally horizontal track surfaceextending along it, pair of elongated track extender members for theopposite ends of each track member, each track extender member beingmounted adjacent its associated track member for movement betweenextended and retracted positions and betweeen raised and loweredpositions relative to such track member, and each including an upwardlyfacing track extension surface extending along it, a track extensionsurface on a track extender member forming an axially alignedlongitudinal extension to a track surface on the associated track memberwith the track extender member in its said extended and raisedpositions, means on each track extender member accommodating detachableconnection thereof to a support external to said vehicle with the trackextender member extended,

a track extender member when extended and so connected moving betweenits raised and lowered positions with adjustment of the elevation ofsaid frame, and

a pair of carriages for each track member and its associated trackextender members ridable on the track surface and track extensionsurfaces thereon, and detachably connectable to the base of a load onsaid deck in the space under the load where such extends beyond an endof a track member,

each carriage being adapted to be engaged and to be picked up by anunderlying track extension surface, thus to pick up a load on said deck,with the track extenders extended, and with adjustment of the elevationof said frame which produces movement of the track extenders from theirsaid lowered toward their said raised position.

1. In a ground-traveling load-transporting vehicle including anelongated frame defining an elongated load-support deck, andground-traveling support means for supporting the frame for travel overthe ground, apparatus facilitating the transfer of a load onto and offof said deck comprising means adjacent said deck defining an elongatedtrack which extends transversely of the frame''s longitudinal axis,opposite ends of said track terminating short of the opposite side ofsaid deck, a pair of elongated movable track extenders mounted on saidframe adjacent the opposite ends of said track for movement betweenextended and retracted positions and between raised and loweredpositions, each track extender when in its said extended and raisedpositions forming a longitudinal extension to an end of said track,means on each track extender accommodating detachable connection thereofto a support external to said vehicle, adjustable suspension meansoperatively interposed between said frame and said ground-travelingsupport means adjustable to suspend the former on the latter atdifferent selected elevations above the ground, adjustment of saidsuspension means producing movement of said track extenders betweentheir said raised and lowered positions with the extenders extended andconnected to external supports, and at least a pair of carriages eachridable on said track and track extenders and each adapted to bedetachably connected to a load on said deck in the space under the loadwhere such extends beyond an end of said track, each carriage furtherbeing adapted to be picked up by an underlying track extender, thus topick up the load, with the track extender extended and with adjustmentof said suspension means which produces movement of the track extenderfrom its said lowered toward its said raised position.
 2. The vehicle ofclaim 1, wherein said means defining said track comprises an eloNgatedtube, and said track extenders are freely and slidably received withinopposite ends of said tube.
 3. The vehicle of claim 2, wherein eachtrack extender is shaped to accommodate limited vertical rocking thereofrelative to said tube with the former extended from the latter.
 4. Anon-board system for transferring a load onto and off of a vehicle, wherethe vehicle includes an elongated frame defining an elongated supportbed for a load, and means supporting the frame for travel over theground and for adjustment to different elevations above the ground, saidsystem comprising a plurality of elongated track members disposedtransversely of said frame''s longitudinal axis and rigidly joined inthe frame at points distributed along the length of said support bed,each track member terminating short of the opposite sides of said bedand including an upwardly facing generally horizontal track surfaceextending along it, a pair of elongated track extender members for theopposite ends of each track member, each track extender member beingmounted adjacent its associated track member for movement betweenextended and retracted positions and betweeen raised and loweredpositions relative to such track member, and each including an upwardlyfacing track extension surface extending along it, a track extensionsurface on a track extender member forming an axially alignedlongitudinal extension to a track surface on the associated track memberwith the track extender member in its said extended and raisedpositions, means on each track extender member accommodating detachableconnection thereof to a support external to said vehicle with the trackextender member extended, a track extender member when extended and soconnected moving between its raised and lowered positions withadjustment of the elevation of said frame, and a pair of carriages foreach track member and its associated track extender members ridable onthe track surface and track extension surfaces thereon, and detachablyconnectable to the base of a load on said deck in the space under theload where such extends beyond an end of a track member, each carriagebeing adapted to be engaged and to be picked up by an underlying trackextension surface, thus to pick up a load on said deck, with the trackextenders extended, and with adjustment of the elevation of said framewhich produces movement of the track extenders from their said loweredtoward their said raised position.